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. (No Model.)

J. A. Mc'GAHY, FIRE ALARM.

No. 573,903. Patented Dec. 29, 1896.

I tothe accompanying drawings, making a part tions included in my invention.

. ranged electric wires, makes known both'by for the pivot a of an armature O. This aris a slot 0' through which .pyojects the, lower tions of parts whereby I provide a self-actthe fire and its locality.

may be of any suitable kind, is provided to rsn JOHN A. MCGAHY, on NEW YORK, N. Y.

FIRE-ALARM.

' SPECIFICATION forming part of Letters Patent No. 573,903, dated December 29,-189l1,

Application filed .April to, 1896.

1'0 all. whom it may concern.- f Be it known that}, Join; A. McG H of the city, county, and State of New York, have invented certain new. and useful Improvements in Fire-Alarms; an (11 do hereby declare that the following is a full, clear, and exact description of the same, reference being had of this specification, in which Flgure 1 is a diagrammatic view of a fire one of the elements entering into combine:

This invention relates to the automatic detection of fires, confiagrations, &c., in dwellings, factories, andother buildings, and it comprises certain new and useful combinaing fire-detector WhichQtlu-ough suitably-ar-- visual and audible signals the occurrence of A is an electromagnet. supported upon a metal bracket B. 'At the upper part of, the latter is an arm B, which provides a bearing mature has atits upper end a horizontal spur b, which carries a weight a, whichtends to throw the armature away from the electric magnet. Near its free extremity the armature has a notch or shoulder (1, below which is an inclined surface a. Abattery B which supply electric energy for the operation of the apparatus. 1

D is a metallic bar pivoted at one end, as at b, and at theother carrying a tag 6, which should project upward at an angle to the bar, substantially as shown in Fig. 1. In this bar.

p rt n of he a maturathe parts-being so proportioned that when the bar is raised to lift the tag into its non-signaling position behind a plate or partition A'- or other hiding or obscuring device, as represented in Fig. 1, the shoulder d of the armature catches under the stop f", formed by the end of. the slot 0, as the armature is swung outward by the weight '0,

thereby retaining the bar and the tag in their Serial No. 589,811. on model.)-

raised positionso long as the armature is kept away from the elec'tromagnet. Arranged below thebar is a contact-piece i From the one pole g of the battery 13 to the contact-piece E extends a wire F. From the same pole g ofthe battery extends another wire Gyhereinafte'r more fully described.

From the opposite pole h of the battery extends a, wire II, which is connected with the one end of the coil of the electromagnet. I The opposite end of said coil is connected to a wire I,which, as hereinafter egzplained, operates in direct conjunction with the .wire G. From the same pole h of the battery extendsawire i K, which connects with'the usual or any suit able mechanismof an' electric bell or audible signal L. A From the bar D extends a wirehl, which connects with the said bellor audible signahoperatiug in connection with the wire K to provide the requisite circuit through the said-audible signal apparatus. In this wire hi is provided a suitable switch 0 by means of which, when desired, such circuit may be madeor broken.

The two wires G and I are brought together,

as at m. For convenience in placingthe wires in the house or structure where the fire-alarm is to be employed eachof these wires may pass to suitable binding-posts a 19 after which they are brought parallel to each other and confined together to form. a cable, as at N.

example, in Fig. 3, in whichthe insulating material of each is shown at f and the ex ternal strata holding them together at 9. They are so constructed that upon an undue 'rise of temperature the insulation f-romeach "other .wili disappear; so that an electric current ,will circuit direct from the one wire to the other at the place where the insulation between them is destroyed.

of the constructor. As shown'in'Fig. 3, they are copper wires, each insulated with anysuitable .fusible or combustible material. As

vcopper, while the other,

against the contact-piece E tablish electric connection between the wires G and I of the cable N is simultaneously signaled audibly and visually by the descent of the tag e and by the automatic the hell or like audible device consequent upon the fall 0fv j device.

\Vhat I claim as my invention is 1. The combination with an electric circuit, means for closing the same from an elevation of temperature, and a battery for supplying the current, of an electromagnet, the armasuch insulating materials are well known in the art, none need be here specifically described. Upon the ignition, combustion, or fusion of the insulatiiigeoverings of the two wires they come into contact with each other in such manner as to permit the transit of the current from one to the other. As shown in Fig. 4, one of the wires, for instance, G, is of- I, is of fusible metal. The two are insulated from each other by any suitable material a, interposed between them, and the two are bound together by an insulating-covcringr common to both. Upon the ture having a counterweight, c, and a notch occurrence of fire along the cableh when thus or shoulder, d, the bar, I), having the tag, 6,

and slot, 0, a contact-piece, E, a wire, F, connecting said contact-piece with one pole of the battery, a hell or audible signaling device, and wires, M, and, K, the one extended from the bar, D, and the other from the batboth to the audible signal, subas and for the purpose herein set formed, the fusible metal of the wire I melts and runs into contact with the wire G, thus establishin g electrical com .nunication between them.

Normally the bar 1) and, of course, the tag 6 are in their elevated position, as shown in ,tery, and full outline in Fig. 1. The wires G and I be- I stantially ing insulated from each other and lying norforth. mally disconnected there is no circuit through I 2. The combination with the clectromagnet, the battery and there is of course no expendil A, armature, having bent arm, bi and counture of energy from the latter. W hen, howtcrwight, c, the bar, I), having sliouldeiyd, ever, the two wires G and I of the cable N are and carrying tag, e, connected by an elevation of temperature, as tery, B and a bell or audible si nal L, of described, a circuit is closed through the wires, I, and, G, united to form ca 1e, N, the eleetromagnet, which, putting the latter in 1 wire F, uniting the contact-pieceI with the operation, attracts the armature O and therebattery, and the wire, IT, extending from the by withdraws its support. from the bar I) and battery to the coil of permits the latter, together with its tag 0, to wires, M, and, K, extended to the audible descend into view. As the tag descends the l signal from the. hai I), baL D- OP the tag, :zsth'e case may be, comes l spectively, all substantially as and for the l I and thereby eompurpose herein set forth. l p etes a circuit thi-ough t 1e bar D, the con- I tact-piece E, the wires F and K, and the wire OHN f M, which actuates the hell or other audible signaling device, so that by the means described the occurrence of a fire sufficient to es- Witnesses:

ALEX. MCGAHY, IIERM. II. PULFs.

sounding oi" the tag or visual signaling a contact-piece, F,'a bat the battery re 

